Re: [PATCH] interpreter_exec_cmd (interps.c)

[Andrew Cagney <cagney@gnu.org>]

Nick Roberts wrote:
> GDB hangs if it receives the previously legitimate command
> server interpreter mi "-var-update *"
> 
> 
> GNU gdb 6.3.50.20050125-cvs
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> 
> (gdb) server interpreter mi "-var-update *"
> ^done,changelist=[]
> (gdb) 
> error in command: "-var-update *".
> 
> 
> The patch below seems to fix it. I don't know what values reason takes as
> struct exception in exception.h has no commented description, so this patch is
> a bit of a guess and may not be the right fix. The bug is real, however.
> There seems to be a further bug, in that once GDB has reached the line in
> interps.c, 
> 
> error ("error in command: \"%s\".", prules[i]),
> 
> ,presumably it shouldn't hang.

Hmm, another example is:

	(gdb) interpreter console help foo

Can you create a new minimal test "gdb.base/interpreter.exp" to sanity 
check one of the above (and add anything else that takes your fancy :-)

Be sure to check that the test actually fails without the test (and 
don't forget to mention the system it was tested on).   Consider that 
pre-approved.

> 
> 
> *** /home/nick/src/gdb/interps.c.~1.10.~	2005-01-16 15:46:17.000000000 +1300
> --- /home/nick/src/gdb/interps.c	2005-01-25 22:47:42.000000000 +1300
> ***************
> *** 399,405 ****
>     for (i = 1; i < nrules; i++)
>       {
>         struct exception e = interp_exec (interp_to_use, prules[i]);
> !       if (!e.reason)

Oops!  e.reason < 0 indicates an error (the [very old] description of 
enum return_reason hints at this).  With that tweak, and the testsuite, 
this is approved.

good catch,
Andrew